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Progress in Natural Science:Materials International 2024年第3期34卷 512-523页

作者： Xin Tong Hao Ye Yunrou wu Xinxing zhan Manqi Gu Shixia Luo Jiangning Gong Juan Tiana Yadian xie School of Chemistry and Material Science Guizhou Normal University Center for the Physics of Low-Dimensional Materials School of Physics and Electronics School of Future Technology Henan University Key Laboratory of Low-Dimensional Materials and Big Data Guizhou Minzu University

High-entropy alloy nanoparticles(HEA-NPs) have recently sparked great interest in materials science. Their solidsolution states, derived from distinct HEA configurations, make them promising candidates for catalysts with exceptional activity, stability, and tunable performance. However, a comprehensive understanding of the underlying mechanisms governing their electrocatalytic behavior is still lacking, hindering the rational design of HEA electrocatalysts. This review summarizes the fundamental knowledge of HEA-NPs, including the structureactivity correlations of HEA-NPs, diverse synthesis strategies, and applications in electrochemical catalysis. The design strategies for guiding improvements in tunable performance were highlighted. The article concludes with insights, perspectives, and future directions, encapsulating the state-of-the-art knowledge and paving the way for further exploration in this dynamic field.

关键词： Electrochemical catalysis High-entropy alloy nanoparticles Structure-activity correlations Synthesis strategies

HOPF BIFURCATION AND UNIQUENESS OF LIMIT CYCLE FOR A CLASS OF QUARTIC SYSTEM

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Applied Mathematics(A Journal of Chinese Universities) 2007年第4期22卷 388-392页

作者： zhan qingyi xie xiangdong wu chengqiang Qiu Shulin Dept. of Comput. and Inform. Fujian Agriculture and Forestry Univ. Fuzhou 350002 China. Dept. of Math. Ningde Normal College Ningde 352100 China. College of Math. and Comput. Sci. Fuzhou Univ. Fuzhou 350002 China. Dept. of Math. Gannan Normal College Ganzhou 341000 China.

This paper studies a class of quartic system which is more general and realistic than the quartic accompanying system.x＇=-y＋ex＋lx^2＋mxy＋ny^2,y＇=x（1-Ay）（1＋Cy^2）,（＊）where C 〉 0. Sufficient conditions are ... 详细信息

关键词： accompanying system, bifurcation limit cycle uniqueness.

基于多通道交叉卷积UCTransNet的双能CT基材料分解方法

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光学学报 2024年第5期44卷 128-142页

作者：吴凡金潼詹郭睿解晶晶刘进张谊坤安徽工程大学计算机与信息学院安徽芜湖241000 计算机网络和信息集成教育部重点实验室(东南大学) 江苏南京210096 东南大学影像科学与技术实验室江苏南京210096

提出一种基于多通道交叉卷积UCTransNet(MC-UCTransNet)的图像域双材料分解方法。该网络以UCTransNet为基础架构,采用通道交叉融合转换器和通道交叉注意模块来提高基材料分解性能,实现双输入双输出的端到端映射。网络中通道交叉融合模... 详细信息

提出一种基于多通道交叉卷积UCTransNet(MC-UCTransNet)的图像域双材料分解方法。该网络以UCTransNet为基础架构,采用通道交叉融合转换器和通道交叉注意模块来提高基材料分解性能,实现双输入双输出的端到端映射。网络中通道交叉融合模块和通道交叉注意模块可更好地捕捉复杂的通道信号相关性,以更充分地进行特征提取与融合,实现基材料生成路径之间的信息交换。为进一步提高模型的拟合性能,网络训练时采用混合损失及Sigmoid函数的归一化方法。实验结果表明,在骨骼基材料及软组织碘基材料分解任务中,所提方法能获得优质的基材料图像,与对比方法相比,其分解后的基材料图像在准确度及噪声伪影抑制上表现更好。

关键词：机器视觉双能计算机断层成像基材料分解多通道交叉卷积注意力噪声抑制

高强CFRP拉索-弯折锚固系统静力性能研究

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中国公路学报 2024年第3期37卷 298-307页

作者：周竞洋汪昕解佳展许淇威吴智深东南大学混凝土及预应力混凝土教育部重点实验室江苏南京211189 玄武岩纤维生产及应用技术国家地方联合工程研究中心江苏南京211189 东南大学城市工程科学技术研究院江苏南京211189

为了满足索承结构对拉索索力增长的需求,增加单筋直径和数量来提升索力是一种有效方法,但同时会导致索体直径和盘卷直径过大。为此,基于先前开发的变刚度锚固荷载传递介质,提出一种采用多根高强小直径CFRP筋的弯折锚固系统(简称弯折锚)... 详细信息

为了满足索承结构对拉索索力增长的需求,增加单筋直径和数量来提升索力是一种有效方法,但同时会导致索体直径和盘卷直径过大。为此,基于先前开发的变刚度锚固荷载传递介质,提出一种采用多根高强小直径CFRP筋的弯折锚固系统(简称弯折锚)来同时提升索力和弯曲性能。针对多筋拉索建模复杂以及计算效率低的问题,提出了基于等效圆环的应力释放模型,并利用足尺试验对应力释放模型的可靠性以及锚固方法的有效性进行验证。结果表明:改变单筋间距有利于减小平行锚最外层筋内外侧轴向拉应力差,但对轴向应力和径向应力影响较小。应力释放模型可以有效解决封闭圆环模型的“环箍效应”,使拉索内层筋的环向挤压应力更加趋近于真实的多筋模型。高强CFRP拉索失效模式为整体炸裂式破坏,荷载传递介质几乎没有受到可见的挤压和剪切损伤。应力释放模型对荷载-位移曲线、轴向位移和锚固区拉索轴向应变均具有较高的模拟精度。Φ4-91高强CFRP拉索的实测极限抗拉力为3 393 kN,相应的锚固效率为91%,而锚固效率低的原因在于多筋受力不均匀和未对锚具进行重新设计。自由段拉索轴向应变随荷载的增加而增大,应变片粘贴位置、胶层厚度以及筋材长度误差是导致轴向应变差过大的主要原因。相同荷载下锚固区中心筋轴向应变自加载端至自由端近似线性减小,锚固区30~360 mm范围内中心筋平均剪应力呈缓慢增长趋势,表明变刚度锚固设计有利于缓解拉索剪应力集中。

关键词：桥梁工程高强CFRP拉索有限元模拟变刚度弯折锚固应力释放足尺试验

GLOBAL ATTRACTIVITY IN AN ALMOST PERIODIC PREDATOR-PREY-MUTUALIST SYSTEM

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Annals of Applied Mathematics 2016年第1期32卷 42-53页

作者： Liya Yang Fengde Chen chengqiang wu xiangdong xie College of Math.and Computer Science Fuzhou University Dept.of Math. Ningde Normal University

In this paper, the almost periodic predator-prey-mutualist model with Holling type II functional response is discussed. A set of sufficient condi- tions which guarantee the uniform persistence and the global attractivity of the system are obtained. For the almost periodic case, by constructing a suit- able Lyapunov function, sufficient conditions which guarantee the existence of a unique globally attractive positive almost periodic solution of the system are obtained. An example together with its numerical simulations shows the feasibility of the main results.

关键词： almost periodic solution predator-prey-mutualist system func-tional response Lyapunov function global attractivity

Structural whiteness of the multi-component glaze dependence on amorphous photonic crystals

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Frontiers of Materials Science 2019年第2期13卷 206-215页

作者： Hongquan zhan Chuanqi wu Ce DENG Xiaohong LI Zhipeng xie Changan WANG School of Materials Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China State Key Lab of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China

A kind of enhancing mechanism of structural whiteness dependence on amorphous photonic crystal (APC) structure is introduced in this paper. In the glaze system composed of albite, kaolin, talc, calcite, quartz, titanium dioxide and zinc oxide, the APC structure will be produced by using quartz as a variable to induce the phase separation. Under different polarities between Ti, Zn etc. and Siion, the separated spheres with the core-shell structure can be obtained and then make up opal-like APCs in the glaze layer. In addition to inner and outer layers of core-shell spheres, the calculated results of refractive indices clearly show the great difference between the particles and the matrix. As a result of different refractive indices, the multiple scatting of visible light plays a key rote in the structural whiteness. However, due to the decrease of the cationic content, APCs with the reverse opal structure would be formed in the interface between glaze and body. Ultimately, the glaze appearance reveals extremely high structural whiteness due to the special APC structure.

关键词： structural whiteness amorphous photonic crystal core-shell structure

Reference values of carotid intima-media thickness and arterial stiffness in Chinese adults based on ultrasound radio frequency signal: A nationwide, multicenter study

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中华医学杂志(英文版) 2024年第15期137卷 2024 Jul 3页

作者： Xing Changyang xie Xiujing wu Yu Xu Lei Guan Xiangping Li Fan zhan Xiaojun Yang Hengli Li Jinsong Zhou Qi Mu Yuming Zhou Qing Ding Yunchuan Wang Yingli Wang Xiangzhu Zheng Yu Sun Xiaofeng Li Hua zhang Chaoxue Zhao Cheng Qiu Shaodong Yan Guozhen Yang Hong Mao Yinjuan zhan Weiwei Ma Chunyan Gu Ying Chen wu xie Mingxing Jiang Tianan Yuan Lijun Department of Ultrasound Medicine Tangdu Hospital Air Force Medical University Xi’an Shaanxi China Department of Ultrasound Medicine The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou Zhejiang China Department of Ultrasound Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei China Department of Ultrasound Xi’an Hospital of Traditional Chinese Medicine Xi’an Shaanxi China Ultrasound Medical Diagnosis Center Shaanxi Provincial People’s Hospital Xi’an Shaanxi China Department of Ultrasound Hospital of Northwestern Polytechnical University Xi’an Shaanxi China Department of Ultrasound Xi’an No. Hospital The First Affiliated Hospital of Northwest University Xi’an Shaanxi China Department of Ultrasound Diagnosis The Second Affiliated Hospital Xi’an Medical College Xi’an Shaanxi China Department of Ultrasound Xi’an Gem Flower ChangQing Hospital Xi’an Shaanxi China Department of Ultrasound The Second Affiliated Hospital of Xi’an Jiaotong University China Xi’an Shaanxi China Department of Echocardiography First Affiliated Hospital of Xinjiang Medical University Urumqi Xinjiang China Department of Ultrasound Renmin Hospital of Wuhan University Wuhan Hubei China Department of Ultrasound Yan’an Hospital The Affiliated Hospital of Kunming Medical University Kunming Yunnan China Department of Ultrasound Yan’an University Xianyang Hospital Xianyang Shaanxi China Department of Function Examination Beijing University of Chinese Medicine Third Affiliated Hospital Beijing China Department of Ultrasound Xi’an Central Hospital Xi’an Shaanxi China Cadre’s Wards Ultrasound Department Diagnostic Ultrasound Center First Hospital of Jilin University Changchun Jilin China Department of Echocardiography Affiliated Hospital of Traditional Chinese Medicine of Xinjiang Medical University Urumqi Xinjiang China Department of Ultrasound First Affiliated Hospital of Anhui Medical University Hefei

Background: Carotid intima-media thickness (IMT) and diameter, stiffness, and wave reflections, are independent and important clinical biomarkers and risk predictors for cardiovascular diseases. The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical ***: A total of 3053 healthy Han Chinese adults (1922 women) aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022. The real-time tracking of common carotid artery walls was achieved by the radio frequency (RF) ultrasound system. The IMT, diameter, compliance coefficient, β stiffness, local pulse wave velocity (PWV), local systolic blood pressure, augmented pressure (AP), and augmentation index (AIx) were then automatically measured and reported. Data were stratified by age groups and sex. The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions. The major clinical determinants of carotid properties were identified by Pearson’s correlation, multiple linear regression, and analyses of ***: All the parameters of carotid properties demonstrated significantly age-related trajectories. Women showed thinner IMT, smaller carotid diameter, larger AP, and AIx than men. The β stiffness and PWV were significantly higher in men than women before forties, but the differences reversed after that. The increase rate of carotid IMT (5.5 μm/year in women and 5.8 μm/year in men) and diameter (0.03 mm/year in both men and women) were similar between men and women. For the stiffness and wave reflections, women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes (allP for age by sex interaction <0.05). The blood pressures, body mass index (BMI), and triglyceride levels were identified as major clinical determinants o

关键词： Intima-media thickness Arterial stiffness Reference values Ultrasound radio frequency signal Wave reflections

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创伤性脑出血体积定量的深度学习方法研究

陆军军医大学学报 2024年第19期46卷 2225-2235页

作者：陈地友时心怡吴鹏飞詹力赵文兵谢静茹张良赵辉陆军特色医学中心放射科重庆400042 陆军特色医学中心军事交通伤防治研究室重庆400042 重庆理工大学两江人工智能学院重庆401135

目的基于Trans-UNet模型构建创伤性脑出血(traumatic intracerebral hemorrhage,TICH)体积定量的深度学习方法,并与公式法进行比较。方法收集我院放射科于2018年5月至2023年5月收治的141例创伤性脑出血患者的CT资料,建立基于Trans-UNet... 详细信息

目的基于Trans-UNet模型构建创伤性脑出血(traumatic intracerebral hemorrhage,TICH)体积定量的深度学习方法,并与公式法进行比较。方法收集我院放射科于2018年5月至2023年5月收治的141例创伤性脑出血患者的CT资料,建立基于Trans-UNet模型的深度学习方法,以影像归档与通讯系统(picture archiving and communication system,PACS)人工勾画为金标准,对比其与公式法(共10种)在创伤性脑出血体积定量的准确性、一致性和测量耗时差异。结果PACS人工勾画的创伤性脑出血中位体积为1.167 mL,单个患者的测量中位时间为135 s。深度学习方法与PACS人工勾画的体积百分误差中位数为3.59%,Spearman相关系数为0.999(P<0.001),单个患者测量的中位时间仅为4.38 s;而公式法中,最低体积百分误差中位数为16.451%,最高Spearman相关系数为0.986(P<0.001),单个患者测量的最低中位时间为20 s。两类方法在体积百分误差和测量时间上的差异均具有统计学意义(P均<0.001)。结论本研究所构建的深度学习方法相较于公式法,在测量准确性和时效上均表现更优。

关键词：创伤性脑出血计算机体层摄影深度学习体积定量创伤性脑损伤

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硅多晶基磷检验中硼和碳的引入分析

云南化工 2024年第10期51卷 131-133页

作者：徐顺波袁秋月谢佳均贾琳吴麟肖翔东四川永祥新能源有限公司四川乐山614000

硅多晶作为超高纯半导体原材料,需要按照标准对其杂质进行检测,从而判定质量等级决定其最终用途。文章通过分析磷基制样过程中硼和碳杂质的情况,探讨了可能引入杂质的来源,并给出了控制建议以达到提高分析结果准确性的目的。

关键词：硅多晶样芯硅单晶硼碳分析

UNIQUENESS OF LIMIT CYCLE FOR A CLASS OF QUARTIC SYSTEM ACCOMPANYING WITH QUADRATIC SYSTEM

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Annals of Differential Equations 2008年第2期24卷 239-245页

作者： zhan qingyi(College of Computer and Information Science,Fujian Agriculture and Forestry University,Fuzhou 350002) xie xiangdong(Dept. of Math.,Ningde Teachers College,Ningde 352100,Fujian) wu chengqiang(College of Math. and Computer Science,Fuzhou University,Fuzhou 350002)

In this paper,we consider a class of quartic system,which is more general and realistic than the quartic accompanying system. Consequently,we obtain sufficient conditions concerning the uniqueness of limit cycle as we... 详细信息

关键词： accompanying system limit cycle uniqueness